Matsudaira Nobuyasu

Matsudaira Nobuyasu (松平 信康^?, 13 April 1559 – 5 October 1579) was the eldest son of Tokugawa Ieyasu. His tsūshō ("common name") was Jirōsaburō (次郎三郎^?). He was called also "Okazaki Saburō" (岡崎 三郎^?), because he had become the lord of Okazaki Castle (岡崎城^?) in 1570. Because he was a son of Tokugawa Ieyasu, he is often referred to, retroactively, as Tokugawa Nobuyasu (徳川 信康^?).

Nobuyasu was Ieyasu's first son. His mother was Imagawa Yoshimoto's niece, Lady Tsukiyama.

As a child Nobuyasu was sent to the Imagawa capital of Sunpu, located in Suruga Province (modern-day Shizuoka Prefecture) as a hostage. Later he was named keeper of Okazaki Castle in Mikawa Province (modern-day Aichi Prefecture), the birthplace of his father, and took part in the Battle of Nagashino in 1575.

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